replicate-couchdb-cluster

1.0.2 • Public • Published

replicate-couchdb-cluster

Greenkeeper badge Circle CI

A fault-tolerant way to replicate an entire CouchDB cluster

Installation

$ npm install -g replicate-couchdb-cluster

Usage

Usage: replicate-couchdb-cluster -s source -t target options

  -s source           The URL for the CouchDB cluster from which we will be
                      replicating

  -t target           The URL for the CouchDB cluster to which we will be
                      replicating

Options:

  -c max-concurrency  The maximum number of concurrent replications. If this
                      value is omitted then the max-concurrency is defaulted
                      to 20.

  -i dbs-to-skip      A comma separated list of DBS to skip

  -a                  Use the target's _replicate API when replicating. This is
                      particularly useful when you are trying to replicate from
                      a remote source to localhost. By default, the source's
                      _replicate API is used.

  -v                  Verbose

  -d                  Debug info such as details of the requests and responses.
                      Useful for determining why long replications are failing.

Examples:

  Replicate all DBs on example1.com to example2.com:

    $ replicate-couchdb-cluster -s http://example1.com:5984 -t http://example2.com:5984

  Replicate all DBs, except the _users and _replicator DBs:

    $ replicate-couchdb-cluster -s http://example1.com:5984 -t http://example2.com:5984 \
                                -i _users,replicator

  Replicate all DBs using SSL and authentication:

    $ replicate-couchdb-cluster -s https://admin1:secrect1@example1.com:6984 \
                                -t https://admin2:secrect2@example2.com:6984

  Replicate all DBs from a remote source to a local source:

    $ replicate-couchdb-cluster -s https://admin1:secrect1@example1.com \
                                -t http://localhost:5984
                                -a

In a docker container

This can be useful for scheduling a reoccurring backup.

Run the replication in the foreground:

$ docker run -it \
    -e SOURCE="https://admin1:secrect1@example1.com:6984" \
    -e TARGET="https://admin2:secrect2@example2.com:6984" \
    redgeoff/replicate-couchdb-cluster

Replicate every hour in the background. This will persist through server reboots:

$ docker run -d --name replicate-couchdb-cluster \
    --restart always \
    -e SOURCE="https://admin1:secrect1@example1.com:6984" \
    -e TARGET="https://admin2:secrect2@example2.com:6984" \
    -e RUN_EVERY_SECS=3600 \
    -e VERBOSE=true \
    redgeoff/replicate-couchdb-cluster

Notes:

  • If the replication takes longer than RUN_EVERY_SECS, it will result to running the replications back to back. You can use RUN_EVERY_SECS=0 if you always want the replication to run continuously.
  • You can view the output at /var/lib/docker/containers/<container id>/<container id>-json.log

Replicate every day at 23:00 UTC (11 PM). This will persist through server reboots:

$ docker run -d --name replicate-couchdb-cluster \
    --restart always \
    -e SOURCE="https://admin1:secrect1@example1.com:6984" \
    -e TARGET="https://admin2:secrect2@example2.com:6984" \
    -e RUN_AT="23:00" \
    -e VERBOSE=true \
    redgeoff/replicate-couchdb-cluster

All options:

$ docker run -d --name replicate-couchdb-cluster \
    --restart always
    -e SOURCE="https://admin1:secrect1@example1.com:6984" \
    -e TARGET="https://admin2:secrect2@example2.com:6984" \
    -e RUN_AT="HH:MM" \
    -e RUN_EVERY_SECS=3600 \
    -e CONCURRENCY=10 \
    -e SKIP="_users,_replicator" \
    -e USE_TARGET_API=1 \
    -e VERBOSE=true \
    -e DEBUG=true \
    redgeoff/replicate-couchdb-cluster

Note: The RUN_AT and RUN_EVERY_SECS options cannot be used simultaneously. RUN_AT will always take precedence over RUN_EVERY_SECS.

API

You can also use the API.

Example:

var replicate = require('replicate-couchdb-cluster');
 
replicate({
  source: https://admin1:secrect1@example1.com:6984,
  target: https://admin2:secrect2@example2.com:6984,
  concurrency: 10,
  skip: ['_users', '_replicator'],
  verbose: true,
  useTargetAPI: true,
  debug: true
}).then(function () {
  // Replication done
});

Why?

You may be wondering why you would need such a tool when CouchDB 2 automatically replicates data between nodes:

  • We feel it is much safer to have a separate backup of our data in case something happens to our data, e.g. we accidentally delete data, there is a hacking attempt, etc...
  • Sometimes you want to replicate a cluster to a different region of the world. (The built-in clustering in CouchDB 2 isn't designed to be used across different regions of the world)
  • In rare cases, we have found that CouchDB sometimes corrupts database files and in these rare cases, we've had to restore data from our backups.

Testing

Building

Dependents (0)

Package Sidebar

Install

npm i replicate-couchdb-cluster

Weekly Downloads

0

Version

1.0.2

License

MIT

Unpacked Size

73.8 kB

Total Files

25

Last publish

Collaborators

  • redgeoff